The observations and inferences you make should lead you to ask questions. We ask lots of questions every day, but most of them are not scientific. Typically, a good scientific question is too complex to be answered by simple observation or library research. It requires setting up an investigation or even a group of investigations.

The question Charles Darwin might have asked after seeing so many different finches was something like this: What caused such diversity of finches on the Galapagos Islands?

Here are some scientific questions you might answer this year during science class by performing investigations:

• What brand of mouthwash kills the most bacteria?
• What type of surface causes the most resistance on an inclined plane?
• What causes the roots of a plant to grow downward and the stem to grow upward?

Use your notes to write a scientific question for the three pictures you have observed in this resource.